Stroke. 2004;35:2735-2739
Published online before print September 9, 2004,
doi: 10.1161/01.STR.0000143156.32467.fd
(Stroke. 2004;35:2735.)
© 2004 American Heart Association, Inc.
Clinically Translated Ischemic Stroke Genomics
James F. Meschia, MD
From the Department of Neurology, Mayo Clinic, Jacksonville, Fla.
Correspondence to Dr James F. Meschia, Department of Neurology, Mayo Clinic, 4500 San Pablo Road, Jacksonville, FL 32224. E-mail meschia.james{at}mayo.edu
 |
Abstract
|
|---|
Cohort studies show that having a positive family history of
stroke increases the odds of having a stroke by

30%. The heritability
of stroke appears to be heterogeneous across ischemic stroke
subtypes, with cardioembolic stroke being least heritable. The
relative influence of stroke risk attenuates with age, but genetics
does not cease to be relevant in later adulthood. Recent family
history and twin studies suggest that genetic factors remain
relevant even beyond the seventh decade of life. One of the
challenges of gene discovery in stroke relates to the complexities
of phenotype. The complexities of phenotype can be addressed
by focusing on individual ischemic stroke subtypes or by studying
intermediate phenotypes like leukaraiosis, which has a heritability
of

70%. Although most stroke genetics research has focused on
the identification of risk factor genes, an independent set
of genes likely influences poststroke outcomes (for example,
apolipoprotein E) and response to drug therapies (example,

-adducin
and diuretic therapy).
Key Words: genetics outcome stroke, ischemic
 |
Introduction
|
|---|
There have been recent successes in stroke genomics, including
the discovery of phosphodiesterase 4D
1 and 5-lipoxygenase activating
protein
2 as potential risk factor genes. This review does not
attempt to catalog the scores of stroke genetics studies that
have been reported over the years, but instead attempts to put
stroke genetics research into a clinical context.
 |
Evidence for Inherited Stroke Risk
|
|---|
Even without sequencing a single gene, there is substantial
evidence for inherited risk of stroke. Cohort, case-control,
and twin studies generally support an inherited risk. Flossmann
et al
3 at the Radcliffe Infirmary recently generated quantitative
estimates of this risk in a systematic review of 3 twin, 33
case-control, and 17 cohort studies identified in a search from
1966 through May 2003. Monozygotic twins had 65% greater odds
than dizygotic twins of being concordant for stroke (ie, both
twins having stroke or neither having stroke). Among case-control
studies, having a positive family history of stroke increased
the odds of stroke by 76%. Among cohort studies, having a positive
family history of stroke increased the odds of having a stroke
by 30%. The most statistically powerful studies found significantly
smaller odds ratios than studies of intermediate and low power,
suggesting publication bias.
Marenberg et al4 reported 35-year follow-up results of the Swedish Twin Registry, which included 21 004 twins born between 1886 and 1925. The concordance rates for stroke mortality were 12.5% for monozygotic male twins and 7.4% for dizygotic male twins (P<0.05). The concordance rates for stroke mortality were 20.6% for monozygotic female twins and 16.4% for dizygotic female twins.
Few studies have assessed the heritability of individual subtypes of ischemic stroke. Two case-control studies of ischemic stroke classified proband stroke type using TOAST criteria.5 Jerrard-Dunne et al6 found that a family history of stroke before the age of 65 years increased the odds of having stroke by 38% after adjusting for age, sex, hypertension, diabetes mellitus, serum cholesterol, and smoking status. Family history of stroke before age 65 years was a risk factor for ischemic stroke overall and for the large-vessel subtype. A family history of stroke before age 65 years was not as significant a risk factor for small-vessel stroke, cardioembolic stroke, or stroke of undetermined cause. Polychronopoulos et al7 found that a family history of stroke was a significant risk factor for ischemic stroke overall and for large-vessel and small-vessel subtypes after adjusting for age, sex, hypertension, smoking, and diabetes. However, family history of stroke was not a significant risk factor for patients with cardioembolic stroke or stroke of undetermined cause. Both studies showed that family history of stroke had the least effect on odds of stroke if the stroke was cardioembolic in cause.6,7
 |
Age at Phenotype Expression and Inherited Risk
|
|---|
The relative influence of genetics on stroke risk attenuates
with age of phenotypic expression. This phenomenon is well illustrated
by the case-control study of Jerrard-Dunne et al
6 of 1000 consecutive
cases with ischemic stroke and 800 controls matched for age
and sex. Subjects were recruited from 2 south London hospitals.
Family history of stroke in first-degree relatives was obtained
by structured interview. A family history of stroke occurring
at any age was not a statistically significant risk factor (odds
ratio [OR], 1.22; 95% confidence interval [CI], 0.90 to 1.39).
However, a family history of stroke occurring in a relative
before the age of 65 years was a significant risk factor (OR
1.38; 95% CI, 1.01 to 1.90).
Jerrard-Dunne et al6 also studied the relationship between age of stroke in the proband and a positive family history of early (occurring by age 65 years) stroke for patients with small-vessel and large-vessel stroke. For probands with small-vessel stroke, a positive family history of early stroke carried an odds ratio for stroke by age 55 years of 3.99. The OR decreased to 2.69 for having a stroke by age 65 years. The OR decreased still further to 1.55 and was no longer significant for having a stroke by age 75 years. For probands with large-vessel stroke, a positive family history of early stroke carried an OR of for stroke at age 55 years of 4.46. The odds ratio decreased to 2.34 for having a stroke by age 65 years. The odds ratio remained significant, but decreased still further to 1.88 for having a stroke by age 75 years.
As the study by Jerrard-Dunne6 illustrates, the risk imparted by family history attenuates with age. It is also well-known that the risk of stroke increases exponentially with age. The question arises whether the genetic component to stroke risk overwhelms the nonspecific increasing risk with age. This was assessed in a prospective family history registry of 310 probands with recent ischemic stroke.8 Regression analyses adjusted for sibship size demonstrated that increasing proband age significantly increased the probability of having a concordant sibling, but not the probability of having a living concordant sibling or the probability of having a concordant parent. Attempts at modeling the relationship using a quadratic function or a 2-stage linear function did not explain the probability of having an affected sibling better than a simple linear model. One interpretation of these findings is that there was no point of inflection where the influence of genetics overwhelmed the influence of aging. Our results argued against limiting affected sibling pair studies to any single group of probands defined by age.9
 |
Approaches to Phenotyping
|
|---|
So-called common or sporadic stroke is a complex phenotype in
terms of the diversity of its clinical presentation and the
diversity of its pathophysiology. Genomic research has approached
the complexity of the phenotype by focusing on the study of
intermediate phenotypes or by focusing on the study of relatively
homogenous individual subtypes of stroke (
Figure). Although
intermediate phenotypes are associated with stroke, they are
not necessarily obligate transitional phases to stroke. Intermediate
phenotypes are analogous to surrogate end points in clinical
trials. Any polymorphism or haplotype found to be associated
with an intermediate phenotype should be validated as a risk
factor for stroke itself.

View larger version (37K):
[in this window]
[in a new window]
|
A, Classical epidemiological model of disease. B, General genetic epidemiological model. C, Schematic of ongoing approaches to stroke genomics, showing the human genome as the "exposure" leading to intermediate phenotypes like hypertension and ultimate phenotypes like large-vessel ischemic stroke. Intermediate phenotypes are not a prerequisite to the occurrence of the ultimate phenotypes. IMT indicates intima-media thickness; VCI, vascular cognitive impairment; WMD, white matter disease.
|
|
Carotid intima-media thickness1012 and leukoaraiosis13,14 are commonly studies intermediate phenotypes for ischemic stroke. They can be treated as quantitative traits, typically yielding more statistical power for a given sample size than could be achieved with a dichotomous trait like stroke status. Carotid intima-media thickness and leukoaraiosis can be measured among individuals who are otherwise asymptomatic for cerebrovascular disease. Therefore, the number of potential study participants is relatively large, extending to asymptomatic and symptomatic individuals.
The heritability of an intermediate phenotype can be substantially greater than the heritability for the ultimate phenotype. The NHLBI twins study estimated heritability as high as 73%.15 Magnetic resonance imaging (MRI) determination of leukoaraiosis volume was assessed as part of the Genetic Epidemiology Network of Arteriopathy study in 483 non-Hispanic white subjects.16 The estimated heritability was 80±10%. Adjustments for sex, age, and systolic blood pressure and brain volume reduced the heritability estimate to 67±11%.
Leukoaraiosis is a risk factor for stroke, but not all polymorphisms that are risk factors for leukoaraiosis are necessarily risk factors for stroke. Cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is caused by genetic mutations in the notch 3 gene.17 The MRI abnormalities seen with CADASIL are strikingly similar to the abnormalities seen with severe sporadic leukoaraiosis.18 Although CADASIL is associated with small-vessel stroke and can even have small-vessel stroke as its presenting feature, CADASIL does not appear to be associated with other types of ischemic stroke.
Numerous genetics researchers have broken ischemic into more clinically homogenous subtypes. Some genetic association studies have supported the notion that phenotypic heterogeneity can parallel genetic heterogeneity. Martiskainen et al have found that A+ genotype for the fibrinogen gene promotor 455A was a powerful predictor of having 3 or more lacunar infarcts (OR, 2.57).19 Myllykangas et al found the Ser447Ter polymorphism of lipoprotein lipase to be negatively associated with infarcts <1.5 centimeters.20 Unfortunately, much of the research into the genetic determinants of stroke subtype has been hampered by the lack of coherent use of classification systems.21
 |
Genetic Determinants of Outcome
|
|---|
There is preclinical evidence for genetic determinants of outcome
after cerebral infarction. Jeffs et al
22 performed an experiment
to identify the genetic component responsible for large infarct
volumes in the stroke-prone spontaneous hypertensive rat (SHRSP)
in response to a focal ischemic insult. They performed a genome
scan in an F2 cross derived from the SHRSP and the normotensive
reference WKY strain. The F2 hybrids were subjected to permanent
MCA occlusion, and infarct volume was assessed histologically.
A genome scan revealed a quantitative trait locus on rat chromosome
5 that accounted for 67% of the total variance in infarct volume.
The microsatellite marker known as
anf sits within the gene
encoding for atrial natriuretic factor. F2 hybrids that were
homozygous for the SHRSP allele (
ss) had the largest infarct
volume (208 mm
3). F2 hybrids heterozygous for the SHRSP allele
(
ws) had an intermediate infarct volume (155.5 mm
3). F2 hybrids
homozygous for the WKY allele (
ww) had the smallest infarct
volume (79.2 mm
3). The effects of the
anf marker on infarct
volume were independent of systolic or mean arterial blood pressure.
In a similar experiment, Gratton et al23 studied determinants of infarct volume assessed by MRI after permanent MCA occlusion in the SHRSP, WKY, and F1 hybrids. Adult SHRSP rats and SHRSP x WKY F1 hybrids had comparable infarct volumes, but both SHRSP strains had significantly larger infarct volumes than the WKY rats. The differences could not be explained by differences in blood pressure.
There have been few studies of determinants of stroke outcomes in humans (Table). Most have focused on apolipoprotein E (apoE) as a possible influence on outcomes in ischemic and hemorrhagic stroke, with mixed results. One might expect that several genes harbor common functional variants that can influence outcomes after stroke. Gene products play a role in mechanisms of cell death, proteolysis of the neurovascular matrix, and the inflammatory cascade triggered by ischemia.24 Powerful nongenetic effects on outcome like duration, location, and severity of the ischemic insult will make identifying genes of even moderate effect challenging.
 |
Stroke Pharmacogenomics
|
|---|
Numerous host genetic factors likely influence the response
to acute stroke pharmacotherapy and pharmacological approaches
to primary and secondary stroke prevention. An example of the
interaction of host genetic factors with response to acute pharmacotherapy
comes from a subgroup analysis of the National Institute of
Neurological Disorders and Stroke tPA Stroke Study.
25 In an
analysis that included 409 patients with an available plasma
sample, investigators studied the interaction of
apoE2 and
apoE4 status on stroke outcome. A treatment versus
apoE4 status interaction
was not detected, even after adjusting for various baseline
covariates known to influence outcome.
ApoE2 status itself was
not associated with 3-month favorable outcomes, but there was
a significant interaction between treatment with tissue plasminogen
activator (tPA) and
apoE2. The odds ratio for the global test
for favorable outcome in patients who were
apoE2-positive and
received tPA versus patients who were
apoE2-negative and received
placebo was 5.4 (
P=0.03). The odds ratio for the global test
for favorable outcome when adjusting for baseline covariates
that predicted outcome was 6.4 for
apoE2-positive patients who
received tPA versus
apoE2-negative patients who received placebo
(
P=0.01). This study shows the potential for using genetic testing
to identify a high-responder population for thrombolytic therapy,
a goal that has mainly been pursued to this point based on identification
of certain MRI signal characteristics.
Stroke pharmacogenomics is likely to be most widely applicable in the outpatient clinic where it could be used to tailor primary and secondary stroke prevention. In a population-based case-control study of patients enrolled in a health maintenance organization, Psaty et al26 looked for an interaction between antihypertensive therapy and a common alpha-adducin gene variant (Gly460Trp) that is associated with renal sodium retention in a salt-sensitive form of hypertension in some patient populations. Among patients with the adducin wild-type genotype, diuretic therapy was not associated with risk of myocardial infarction or stroke. However, among the 385 carriers of the adducin gene variant, diuretic therapy was associated with a lower risk of myocardial infarction and stroke than other antihypertensive therapies (OR, 0.49). The current practice of selecting among the various antihypertensive agents, including diuretics, beta blockers, calcium channel blockers, angiotensin-converting enzyme inhibitors, and angiotensin receptor blockers, has been based on practical considerations of cost and side effects as well as nongenetic characteristics of individual patients.27 However, the study by Psaty et al26 suggests that more effective stroke prophylaxis may eventually be based on specific genetic information.
Current secondary stroke prevention is tailored without the use of genetic information based on the presence or absence of comorbidities like atrial fibrillation or symptomatic moderate-grade to high-grade carotid stenosis. In the Warfarin-Aspirin Recurrent Stroke Study (WARSS),28 investigators looked for but did not find a difference between aspirin and warfarin in the prevention of recurrent ischemic stroke or death or in rates of intracranial hemorrhage over a 2-year period of follow-up. In a cohort study within WARSS, Levine et al29 found that the presence of antiphospholipid antibodies (either lupus anticoagulant or anticardiolipin antibodies) among patients with ischemic stroke did not predict either increased risk of subsequent vascular occlusive events or a differential response to aspirin or warfarin. Nor was a differential response to aspirin versus warfarin detected based on patent foramen ovale status in a transesophageal echocardiography substudy.30 It is possible that within the WARSS noncardioembolic nonatherosclerotic stroke population, there may have been patients who responded differentially to aspirin or warfarin. However, at this time there is no practical, reliable means of separating out the high-responders versus low-responders for either therapy. Pharmacogenomics may allow for selection of high-responder versus low-responder populations to antithrombotic drug regimens in the future.
The African-American Antiplatelet Stroke Prevention Study (AAASPS)31 calls into question the value of racial/ethnic status as a means of identifying high-responder versus low-responder populations in secondary stroke prevention. AAASPS was a randomized double-blind multicenter trial of aspirin versus ticlopidine for secondary stroke prevention among 1809 black men and women who had recently had a noncardioembolic ischemic stroke. During a 2-year follow-up, investigators found no significant difference between ticlopidine and aspirin in the prevention of recurrent stroke, myocardial infarction, or vascular death. The rationale for the study relied mainly on a subgroup analysis of the Ticlopidine Aspirin Stroke Study (TASS), which suggested a more favorable risk benefit profile for nonwhites than whites.32 Associated demographic variables are unlikely to be adequate substitutes for molecular genetic information.
 |
Conclusion
|
|---|
Taking model-free genome-wide approaches to gene discovery can
seem like a fishing expedition. The human genome has so many
single nucleotide polymorphisms and even more potential genotype
combinations that the nets that have been cast are weighed down
by the so-called curse of dimensionality.
33 Fortunately, methods
of data mining continue to advance. Recent successes using the
Iceland Healthcare Database demonstrate that genomic approaches
to stroke can yield specific risk factor genes. Genetic testing
will likely have a routine role in optimizing prevention and
treatment of stroke.
Received May 19, 2004;
revision received May 19, 2004;
accepted August 5, 2004.
 |
References
|
|---|
- Gretarsdottir S, Thorleifsson G, Reynisdottir ST, Manolescu A, Jonsdottir S, Jonsdottir T, Gudmundsdottir T, Bjarnadottir SM, Einarsson OB, Gudjonsdottir HM, Hawkins M, Gudmundsson G, Gudmundsdottir H, Andrason H, Gudmundsdottir AS, Sigurdardottir M, Chou TT, Nahmias J, Goss S, Sveinbjornsdottir S, Valdimarsson EM, Jakobsson F, Agnarsson U, Gudnason V, Thorgeirsson G, Fingerle J, Gurney M, Gudbjartsson D, Frigge ML, Kong A, Stefansson K, Gulcher JR. The gene encoding phosphodiesterase 4D confers risk of ischemic stroke. Nat Genet. 2003; 35: 131138.[CrossRef][Medline]
[Order article via Infotrieve]
- Helgadottir A, Manolescu A, Thorleifsson G, Gretarsdottir S, Jonsdottir H, Thorsteinsdottir U, Samani NJ, Gudmundsson G, Grant SF, Thorgeirsson G, Sveinbjornsdottir S, Valdimarsson EM, Matthiasson SE, Johannsson H, Gudmundsdottir O, Gurney ME, Sainz J, Thorhallsdottir M, Andresdottir M, Frigge ML, Topol EJ, Kong A, Gudnason V, Hakonarson H, Gulcher JR, Stefansson K. The gene encoding 5-lipoxygenase activating protein confers risk of myocardial infarction and stroke. Nat Genet. 2004; 36: 233239.[CrossRef][Medline]
[Order article via Infotrieve]
- Flossmann E, Schulz UG, Rothwell PM. Systematic review of methods and results of studies of the genetic epidemiology of ischemic stroke. Stroke. 2004; 35: 212227.[Abstract/Free Full Text]
- Marenberg ME, Zdravkovic S, Pedersen NL, deFair U. The effect of age on the genetic susceptibility to mortality from stroke in men and women: 35 years of follow-up in the Swedish Twin Registry.29th International Stroke Conference, San Diego, Calif; 2004.
- Adams HP, Jr, Bendixen BH, Kappelle LJ, Biller J, Love BB, Gordon DL, Marsh EE, III. Classification of subtype of acute ischemic stroke. Definitions for use in a multicenter clinical trial. TOAST. Trial of Org 10172 in Acute Stroke Treatment. Stroke. 1993; 24: 3541.[Abstract/Free Full Text]
- Jerrard-Dunne P, Cloud G, Hassan A, Markus HS. Evaluating the genetic component of ischemic stroke subtypes: a family history study. Stroke. 2003; 34: 13641369.[Abstract/Free Full Text]
- Polychronopoulos P, Gioldasis G, Ellul J, Metallinos IC, Lekka NP, Paschalis C, Papapetropoulos T. Family history of stroke in stroke types and subtypes. J Neurol Sci. 2002; 195: 117122.[CrossRef][Medline]
[Order article via Infotrieve]
- Meschia JF, Atkinson EJ, OBrien PC, Brott TG, Brown RD, Jr., Hardy J. Familial clustering of stroke according to proband age at onset of presenting ischemic stroke. Stroke. 2003; 34: e89e91.[Abstract/Free Full Text]
- Peto R, Doll R. There is no such thing as aging. BMJ. 1997; 315: 10301032.[Free Full Text]
- Sayed-Tabatabaei FA, Houwing-Duistermaat JJ, van Duijn CM, Witteman JC. Angiotensin-converting enzyme gene polymorphism and carotid artery wall thickness: a meta-analysis. Stroke. 2003; 34: 16341639.[Abstract/Free Full Text]
- Netea MG, Hijmans A, van Wissen S, Smilde TJ, Trip MD, Kullberg BJ, de Boo T, Van der Meer JW, Kastelein JJ, Stalenhorf AF. Toll-like receptor-4 Asp299Gly polymorphism does not influence progression of atherosclerosis in patients with familial hypercholesterolaemia. Eur J Clin Invest. 2004; 34: 9499.[CrossRef][Medline]
[Order article via Infotrieve]
- Fox CS, Larson MG, Corey D, Feng D, Lindpaintner K, Polak JF, Wolf PA, DAgostino RB, Tofler GH, ODonnell CJ. Absence of association between polymorphisms in the hemostatic factor pathway genes and carotid intimal medial thickness: the Framingham Heart Study. Stroke. 2004; 35: e6567.[Abstract/Free Full Text]
- Hassan A, Lansbury A, Catto AJ, Guthrie A, Spencer J, Craven C, Grant PJ, Bamford JM. Angiotensin converting enzyme insertion/deletion genotype is associated with leukoaraiosis in lacunar syndromes. J Neurol Neurosurg Psychiatry. 2002; 72: 343346.[Abstract/Free Full Text]
- Kohara K, Fujisawa M, Ando F, Tabara Y, Niino N, Miki T, Shimokata H. MTHFR gene polymorphism as a risk factor for silent brain infarcts and white matter lesions in the Japanese general population: The NILS-LSA Study. Stroke. 2003; 34: 11301135.[Abstract/Free Full Text]
- Carmelli D, DeCarli C, Swan GE, Jack LM, Reed T, Wolf PA, Miller BL. Evidence for genetic variance in white matter hyperintensity volume in normal elderly male twins. Stroke. 1998; 29: 11771181.[Abstract/Free Full Text]
- Turner ST, Jack CR, Fornage M, Mosley TH, Boerwinkle E, de Andrade M. Heritability of leukoaraiosis in hypertensive sibships. Hypertension. 2004; 43: 483487.[Abstract/Free Full Text]
- Donahue CP, Kosik KS. Distribution pattern of Notch3 mutations suggests a gain-of-function mechanism for CADASIL. Genomics. 2004; 83: 5965.[CrossRef][Medline]
[Order article via Infotrieve]
- van den Boom R, Lesnik Oberstein SA, Ferrari MD, Haan J, van Buchem MA. Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy: MR imaging findings at different ages3rd6th decades. Radiology. 2003; 229: 683690.[Abstract/Free Full Text]
- Martiskainen M, Pohjasvaara T, Mikkelsson J, Mantyla R, Kunnas T, Laippala P, Ilveskoski E, Kaste M, Karhunen PJ, Erkinjuntti T. Fibrinogen gene promoter 455 A allele as a risk factor for lacunar stroke. Stroke. 2003; 34: 886891.[Abstract/Free Full Text]
- Myllykangas L, Polvikoski T, Sulkava R, Notkola IL, Rastas S, Verkkoniemi A, Tienari PJ, Niinisto L, Hardy J, Perez-Tur J, Kontula K, Haltia M. Association of lipoprotein lipase Ser447Ter polymorphism with brain infarction: a population-based neuropathological study. Ann Med. 2001; 33: 486492.[Medline]
[Order article via Infotrieve]
- Meschia JF. Addressing the heterogeneity of the ischemic stroke phenotype in human genetics research. Stroke. 2002; 33: 27702774.[Abstract/Free Full Text]
- Jeffs B, Clark JS, Anderson NH, Gratton J, Brosnan MJ, Gauguier D, Reid JL, Macrae IM, Dominiczak AF. Sensitivity to cerebral ischaemic insult in a rat model of stroke is determined by a single genetic locus. Nat Genet. 1997; 16: 364367.[CrossRef][Medline]
[Order article via Infotrieve]
- Gratton JA, Sauter A, Rudin M, Lees KR, McColl J, Reid JL, Dominiczak AF, Macrae IM. Susceptibility to cerebral infarction in the stroke-prone spontaneously hypertensive rat is inherited as a dominant trait. Stroke. 1998; 29: 690694.[Abstract/Free Full Text]
- Lo EH, Dalkara T, Moskowitz MA. Mechanisms, challenges and opportunities in stroke. Nat Rev Neurosci. 2003; 4: 399415.[Medline]
[Order article via Infotrieve]
- Broderick J, Lu M, Jackson C, Pancioli A, Tilley BC, Fagan SC, Kothari R, Levine SR, Marler JR, Lyden PD, Haley EC, Jr., Brott T, Grotta JC. Apolipoprotein E phenotype and the efficacy of intravenous tissue plasminogen activator in acute ischemic stroke. Ann Neurol. 2001; 49: 736744.[CrossRef][Medline]
[Order article via Infotrieve]
- Psaty BM, Smith NL, Heckbert SR, Vos HL, Lemaitre RN, Reiner AP, Siscovick DS, Bis J, Lumley T, Longstreth WT, Jr., Rosendaal FR. Diuretic therapy, the alpha-adducin gene variant, and the risk of myocardial infarction or stroke in persons with treated hypertension. JAMA. 2002; 287: 16801689.[Abstract/Free Full Text]
- Chobanian AV, Bakris GL, Black HR, Cushman WC, Green LA, Izzo JL, Jr., Jones DW, Materson BJ, Oparil S, Wright JT, Jr, Roccella EJ. The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure: the JNC 7 report. JAMA. 2003; 289: 25602572.[Abstract/Free Full Text]
- Mohr JP, Thompson JLP, Lazar RM, Levin B, Sacco RL, Furie KL, Kistler JP, Albers GW, Pettigrew LC, Adams HP, Jackson CM, Pullicino P. A comparison of warfarin and aspirin for the prevention of recurrent ischemic stroke. N Engl J Med. 2001; 345: 14441451.[Abstract/Free Full Text]
- Levine SR, Brey RL, Tilley BC, Thompson JL, Sacco RL, Sciacca RR, Murphy A, Lu Y, Costigan TM, Rhine C, Levin B, Triplett DA, Mohr JP. Antiphospholipid antibodies and subsequent thrombo-occlusive events in patients with ischemic stroke. JAMA. 2004; 291: 576584.[Abstract/Free Full Text]
- Homma S, Sacco RL, Di Tullio MR, Sciacca RR, Mohr JP. Effect of medical treatment in stroke patients with patent foramen ovale: patent foramen ovale in Cryptogenic Stroke Study. Circulation. 2002; 105: 26252631.[Abstract/Free Full Text]
- Gorelick PB, Richardson D, Kelly M, Ruland S, Hung E, Harris Y, Kittner S, Leurgans S. Aspirin and ticlopidine for prevention of recurrent stroke in black patients: a randomized trial. JAMA. 2003; 289: 29472957.[Abstract/Free Full Text]
- Weisberg LA. The efficacy and safety of ticlopidine and aspirin in non-whites: analysis of a patient subgroup from the Ticlopidine Aspirin Stroke Study. Neurology. 1993; 43: 2731.
- Moore JH, Ritchie MD. The challenges of whole-genome approaches to common diseases. JAMA. 2004; 291: 16421643.[Free Full Text]
- Treger I, Froom P, Ring H, Friedman G. Association between apolipoprotein E4 and rehabilitation outcome in hospitalized ischemic stroke patients. Arch Phys Med Rehabil. 2003; 84: 973976.[CrossRef][Medline]
[Order article via Infotrieve]
- McCarron MO, Muir KW, Nicoll JA, Stewart J, Currie Y, Brown K, Bone I. Prospective study of apolipoprotein E genotype and functional outcome following ischemic stroke. Arch Neurol. 2000; 57: 14801484.[Abstract/Free Full Text]
- Dunn LT, Stewart E, Murray GD, Nicoll JA, Teasdale GM. The influence of apolipoprotein E genotype on outcome after spontaneous subarachnoid hemorrhage: a preliminary study. Neurosurgery. 2001; 48: 10061011.[CrossRef][Medline]
[Order article via Infotrieve]
- McCarron MO, Muir KW, Weir CJ, Dyker AG, Bone I, Nicoll JA, Lees KR. The apolipoprotein E epsilon 4 allele and outcome in cerebrovascular disease. Stroke. 1998; 29: 18821887.[Abstract/Free Full Text]
- Liu Y, Laakso MP, Karonen JO, Vanninen RL, Nuutinen J, Soimakallio S, Aronen HJ. Apolipoprotein E polymorphism and acute ischemic stroke: a diffusion- and perfusion-weighted magnetic resonance imaging study. J Cereb Blood Flow Metab. 2002; 22: 13361342.[CrossRef][Medline]
[Order article via Infotrieve]
- Carter AM, Catto AJ, Bamford JM, Grant PJ. Association of the platelet glycoprotein IIb HPA-3 polymorphism with survival after acute ischemic stroke. Stroke. 1999; 30: 26062611.[Abstract/Free Full Text]
- Carter AM, Catto AJ, Grant PJ. Association of the alpha-fibrinogen Thr312Ala polymorphism with poststroke mortality in subjects with atrial fibrillation. Circulation. 1999; 99: 24232426.[Abstract/Free Full Text]